diff --git a/hutool-core/src/main/java/org/dromara/hutool/core/data/id/Snowflake.java b/hutool-core/src/main/java/org/dromara/hutool/core/data/id/Snowflake.java
index 229674b20..7ab196978 100644
--- a/hutool-core/src/main/java/org/dromara/hutool/core/data/id/Snowflake.java
+++ b/hutool-core/src/main/java/org/dromara/hutool/core/data/id/Snowflake.java
@@ -15,7 +15,6 @@ package org.dromara.hutool.core.data.id;
import org.dromara.hutool.core.date.SystemClock;
import org.dromara.hutool.core.lang.Assert;
import org.dromara.hutool.core.lang.tuple.Pair;
-import org.dromara.hutool.core.text.StrUtil;
import org.dromara.hutool.core.util.RandomUtil;
import java.io.Serializable;
@@ -53,11 +52,6 @@ public class Snowflake implements Serializable {
* 默认的起始时间，为Thu, 04 Nov 2010 01:42:54 GMT
*/
public static long DEFAULT_TWEPOCH = 1288834974657L;
- /**
- * 默认回拨时间，2S
- */
- public static long DEFAULT_TIME_OFFSET = 2000L;
-
private static final long WORKER_ID_BITS = 5L;
// 最大支持机器节点数0~31，一共32个
@SuppressWarnings({"PointlessBitwiseExpression", "FieldCanBeLocal"})
@@ -84,10 +78,6 @@ public class Snowflake implements Serializable {
private final long workerId;
private final long dataCenterId;
private final boolean useSystemClock;
- /**
- * 允许的时钟回拨毫秒数
- */
- private final long timeOffset;
/**
* 当在低频模式下时，序号始终为0，导致生成ID始终为偶数
* 此属性用于限定一个随机上限，在不同毫秒下生成序号时，给定一个随机数，避免偶数问题。
@@ -146,20 +136,9 @@ public class Snowflake implements Serializable {
* @param isUseSystemClock 是否使用{@link SystemClock} 获取当前时间戳
* @since 5.1.3
*/
- public Snowflake(final Date epochDate, final long workerId, final long dataCenterId, final boolean isUseSystemClock) {
- this(epochDate, workerId, dataCenterId, isUseSystemClock, DEFAULT_TIME_OFFSET);
- }
-
- /**
- * @param epochDate 初始化时间起点（null表示默认起始日期）,后期修改会导致id重复,如果要修改连workerId dataCenterId，慎用
- * @param workerId 工作机器节点id
- * @param dataCenterId 数据中心id
- * @param isUseSystemClock 是否使用{@link SystemClock} 获取当前时间戳
- * @param timeOffset 允许时间回拨的毫秒数
- * @since 5.8.0
- */
- public Snowflake(final Date epochDate, final long workerId, final long dataCenterId, final boolean isUseSystemClock, final long timeOffset) {
- this(epochDate, workerId, dataCenterId, isUseSystemClock, timeOffset, 0);
+ public Snowflake(final Date epochDate, final long workerId, final long dataCenterId,
+ final boolean isUseSystemClock) {
+ this(epochDate, workerId, dataCenterId, isUseSystemClock, 0);
}
/**
@@ -167,17 +146,15 @@ public class Snowflake implements Serializable {
* @param workerId 工作机器节点id
* @param dataCenterId 数据中心id
* @param isUseSystemClock 是否使用{@link SystemClock} 获取当前时间戳
- * @param timeOffset 允许时间回拨的毫秒数
* @param randomSequenceLimit 限定一个随机上限，在不同毫秒下生成序号时，给定一个随机数，避免偶数问题，0表示无随机，上限不包括值本身。
* @since 5.8.0
*/
public Snowflake(final Date epochDate, final long workerId, final long dataCenterId,
- final boolean isUseSystemClock, final long timeOffset, final long randomSequenceLimit) {
+ final boolean isUseSystemClock, final long randomSequenceLimit) {
this.twepoch = (null != epochDate) ? epochDate.getTime() : DEFAULT_TWEPOCH;
this.workerId = Assert.checkBetween(workerId, 0, MAX_WORKER_ID);
this.dataCenterId = Assert.checkBetween(dataCenterId, 0, MAX_DATA_CENTER_ID);
this.useSystemClock = isUseSystemClock;
- this.timeOffset = timeOffset;
this.randomSequenceLimit = Assert.checkBetween(randomSequenceLimit, 0, SEQUENCE_MASK);
}
@@ -219,19 +196,16 @@ public class Snowflake implements Serializable {
public synchronized long nextId() {
long timestamp = genTime();
if (timestamp < this.lastTimestamp) {
- if (this.lastTimestamp - timestamp < timeOffset) {
- // 容忍指定的回拨，避免NTP校时造成的异常
- timestamp = lastTimestamp;
- } else {
- // 如果服务器时间有问题(时钟后退) 报错。
- throw new IllegalStateException(StrUtil.format("Clock moved backwards. Refusing to generate id for {}ms", lastTimestamp - timestamp));
- }
+ timestamp = lastTimestamp;
}
if (timestamp == this.lastTimestamp) {
+ // 时间出现回拨，递增序号
final long sequence = (this.sequence + 1) & SEQUENCE_MASK;
if (sequence == 0) {
- timestamp = tilNextMillis(lastTimestamp);
+ // 如果序号耗尽，不再等待时间追赶，而是采用“超前消费”方式，让时间递增。
+ // 这样可以避免系统暂停等待，而选择在“未来”ID新增不快时追上来。
+ timestamp += 1;
}
this.sequence = sequence;
} else {
@@ -295,27 +269,6 @@ public class Snowflake implements Serializable {
}
// ------------------------------------------------------------------------------------------------------------------------------------ Private method start
-
- /**
- * 循环等待下一个时间
- *
- * @param lastTimestamp 上次记录的时间
- * @return 下一个时间
- */
- private long tilNextMillis(final long lastTimestamp) {
- long timestamp = genTime();
- // 循环直到操作系统时间戳变化
- while (timestamp == lastTimestamp) {
- timestamp = genTime();
- }
- if (timestamp < lastTimestamp) {
- // 如果发现新的时间戳比上次记录的时间戳数值小，说明操作系统时间发生了倒退，报错
- throw new IllegalStateException(
- StrUtil.format("Clock moved backwards. Refusing to generate id for {}ms", lastTimestamp - timestamp));
- }
- return timestamp;
- }
-
/**
* 生成时间戳
*
diff --git a/hutool-core/src/test/java/org/dromara/hutool/core/lang/SnowflakeTest.java b/hutool-core/src/test/java/org/dromara/hutool/core/lang/SnowflakeTest.java
index 23f0c99b6..1fb284f2e 100644
--- a/hutool-core/src/test/java/org/dromara/hutool/core/lang/SnowflakeTest.java
+++ b/hutool-core/src/test/java/org/dromara/hutool/core/lang/SnowflakeTest.java
@@ -94,7 +94,7 @@ public class SnowflakeTest {
@Disabled
public void snowflakeRandomSequenceTest(){
final Snowflake snowflake = new Snowflake(null, 0, 0,
- false, Snowflake.DEFAULT_TIME_OFFSET, 2);
+ false, 2);
for (int i = 0; i < 1000; i++) {
final long id = snowflake.nextId();
Console.log(id);
@@ -107,7 +107,7 @@ public class SnowflakeTest {
public void uniqueOfRandomSequenceTest(){
// 测试并发环境下生成ID是否重复
final Snowflake snowflake = new Snowflake(null, 0, 0,
- false, Snowflake.DEFAULT_TIME_OFFSET, 100);
+ false, 100);
final Set ids = new ConcurrentHashSet<>();
ThreadUtil.concurrencyTest(100, () -> {